The Gunnison River in the Black Canyon. The Painted Wall is at right, with light colored magma intrusions in the mostly precambrian-era rock. [1.7 billion years old]. Black Canyon of the Gunnison Na

0402-1001CR ~ Copyright: George H. H. Huey ~ The Gunnison River in the Black Canyon. The Painted Wall is at right, with light colored magma intrusions in the mostly precambrian-era rock. [1.7 billion years old]. Black Canyon of the Gunnison National Park, Colorado.